Magnetic contact switch (door sensor)

Product ID: 375
Qty Discount
1-9 $3.95
10-99 $3.56
100+ $3.16


This sensor is essentially a reed switch, encased in an ABS plastic shell. Normally the reed is 'open' (no connection between the two wires). The other half is a magnet. When the magnet is less than 13mm (0.5") away, the reed switch closes. They're often used to detect when a door or drawer is open, which is why they have mounting tabs and screws. You can also pick up some double-sided foam tape from a hardware store to mount these, that works well without needing screws.

Technical Details

Revision History: As of June 2, 2021, we now have these with premium wire ends for easy breadboarding.

  • Normally open reed switch
  • ABS enclosure
  • Rated current: 100 mA max
  • Rated voltage: 200 VDC max
  • Distance: 15mm max


  • Box size (each side): 29mm x 15.2mm x 9mm
  • Cable Length: ~29cm / ~11.4"
RoHS 2 2011 65 EU Compliant
RoHS 2 2015 863 EU Compliant


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